Adding a data point here, and a question for @starecho specifically.
I'm hitting the identical symptoms on a standalone watchOS app (no iOS
companion, WKApplication + WKWatchOnly, single native target):
Xcode Organizer → Distribute App: no "App Store Connect" option for
this app type, only ad-hoc/development.
xcodebuild -exportArchive -method app-store-connect: exit code 70.
Xcode Cloud reproduces the same failure.
xcrun altool --upload-app --type watchos:
"Cannot determine the 'platform' from the info.plist. (19)"
Apple Transporter: "Could not create a temporary .itmsp package for
the app. Failed to get the enum string for platform ID 6."
Environment: macOS Tahoe 26.2 (25C56), Xcode 26.5 (17F42) and Xcode
26.6 RC2 (18B5054e) — both affected identically.
@starecho's explanation matches my project structure exactly: my
project.pbxproj has a single native target, SDKROOT=watchos, no iOS
container target at all — built that way from the start (not an older
project that had one removed). If Xcode 26's watch-only template really
does auto-generate a hidden …watchapp2-container (SDKROOT=iphoneos)
target that wraps a …watchkitapp-suffixed watch target, and that
container is what makes the archive distributable, that would explain
every error above precisely: the tooling is trying to resolve a
platform/container structure that a bare single-SDKROOT=watchos archive
doesn't have.
Has anyone actually confirmed adding that container target fixes the
upload? I'm about to try recreating the target via Xcode's current
watch-only template and porting sources into the resulting two-target
structure — will report back either way. Also flagging this matches
Feedback reports FB22730778 and FB23341311 if anyone wants to cross-file.
Thanks all — this thread is the most useful lead I've found on this bug.
