diff --git a/Source/ARTRest+Private.h b/Source/ARTRest+Private.h
index be2f284ab..8f2014ff6 100644
--- a/Source/ARTRest+Private.h
+++ b/Source/ARTRest+Private.h
@@ -21,6 +21,8 @@ ART_ASSUME_NONNULL_BEGIN
 @property (readonly, strong, nonatomic) __GENERIC(id, ARTEncoder) defaultEncoder;
 @property (readonly, strong, nonatomic) NSString *defaultEncoding; //Content-Type
 @property (readonly, strong, nonatomic) NSDictionary *encoders;
+
+// Private prioritized host for testing only (overrides the current `restHost`)
 @property (readwrite, strong, nonatomic, art_nullable) NSString *prioritizedHost;
 
 @property (nonatomic, strong) id<ARTHTTPExecutor> httpExecutor;
diff --git a/Source/ARTRest.m b/Source/ARTRest.m
index 099a56f60..9a65dfb22 100644
--- a/Source/ARTRest.m
+++ b/Source/ARTRest.m
@@ -153,7 +153,7 @@ - (void)executeRequest:(NSMutableURLRequest *)request completion:(void (^)(NSHTT
             }
         }
         if (retries < _options.httpMaxRetryCount && [self shouldRetryWithFallback:request response:response error:error]) {
-            if (!blockFallbacks && [request.URL.host isEqualToString:(_prioritizedHost ? _prioritizedHost : [ARTDefault restHost])]) {
+            if (!blockFallbacks && [request.URL.host isEqualToString:[self currentHost]]) {
                 blockFallbacks = [[ARTFallback alloc] initWithOptions:_options];
             }
             if (blockFallbacks) {
@@ -189,6 +189,14 @@ - (BOOL)shouldRetryWithFallback:(NSMutableURLRequest *)request response:(NSHTTPU
     return NO;
 }
 
+- (NSString *)currentHost {
+    if (_prioritizedHost) {
+        // Test purpose only
+        return _prioritizedHost;
+    }
+    return self.options.restHost;
+}
+
 - (void)prepareAuthorisationHeader:(ARTAuthMethod)method completion:(void (^)(NSString *authorization, NSError *error))callback {
     [self prepareAuthorisationHeader:method force:NO completion:callback];
 }
diff --git a/Spec/RestClient.swift b/Spec/RestClient.swift
index 487115620..e65faee50 100644
--- a/Spec/RestClient.swift
+++ b/Spec/RestClient.swift
@@ -786,7 +786,7 @@ class RestClient: QuickSpec {
                 }
 
                 // RSC15e
-                it("every new HTTP request is first attempted to the primary host rest.ably.io") {
+                it("every new HTTP request is first attempted to the default primary host rest.ably.io") {
                     let options = ARTClientOptions(key: "xxxx:xxxx")
                     options.httpMaxRetryCount = 1
                     let client = ARTRest(options: options)
@@ -812,9 +812,44 @@ class RestClient: QuickSpec {
                     if testHTTPExecutor.requests.count != 3 {
                         return
                     }
-                    expect(NSRegularExpression.match(testHTTPExecutor.requests[0].URL!.absoluteString, pattern: "//rest.ably.io")).to(beTrue())
+
+                    expect(NSRegularExpression.match(testHTTPExecutor.requests[0].URL!.absoluteString, pattern: "//\(ARTDefault.restHost())")).to(beTrue())
+                    expect(NSRegularExpression.match(testHTTPExecutor.requests[1].URL!.absoluteString, pattern: "//[a-e].ably-realtime.com")).to(beTrue())
+                    expect(NSRegularExpression.match(testHTTPExecutor.requests[2].URL!.absoluteString, pattern: "//\(ARTDefault.restHost())")).to(beTrue())
+                }
+
+                // RSC15e
+                it("if ClientOptions#restHost is set then every new HTTP request should first attempt ClientOptions#restHost") {
+                    let options = ARTClientOptions(key: "xxxx:xxxx")
+                    options.httpMaxRetryCount = 1
+                    options.restHost = "fake.ably.io"
+                    let client = ARTRest(options: options)
+                    client.httpExecutor = testHTTPExecutor
+                    testHTTPExecutor.http = MockHTTP(network: .HostUnreachable)
+                    let channel = client.channels.get("test")
+
+                    waitUntil(timeout: testTimeout) { done in
+                        channel.publish(nil, data: "nil") { _ in
+                            done()
+                        }
+                    }
+
+                    testHTTPExecutor.http = ARTHttp()
+
+                    waitUntil(timeout: testTimeout) { done in
+                        channel.publish(nil, data: "nil") { _ in
+                            done()
+                        }
+                    }
+
+                    expect(testHTTPExecutor.requests).to(haveCount(3))
+                    if testHTTPExecutor.requests.count != 3 {
+                        return
+                    }
+
+                    expect(NSRegularExpression.match(testHTTPExecutor.requests[0].URL!.absoluteString, pattern: "//\(client.options.restHost)")).to(beTrue())
                     expect(NSRegularExpression.match(testHTTPExecutor.requests[1].URL!.absoluteString, pattern: "//[a-e].ably-realtime.com")).to(beTrue())
-                    expect(NSRegularExpression.match(testHTTPExecutor.requests[2].URL!.absoluteString, pattern: "//rest.ably.io")).to(beTrue())
+                    expect(NSRegularExpression.match(testHTTPExecutor.requests[2].URL!.absoluteString, pattern: "//\(client.options.restHost)")).to(beTrue())
                 }
 
                 // RSC15a