Update UT constants and add helper function to UTChannelID

Cherry-pick of !534 (merged) to 2024-patches - skipping separate approvals as everything was already approved at !534 (merged).

Part of the set: Moore!2754 (merged), Rec!3708 (merged), LHCb!4364 (merged), Alignment!440 (merged), DaVinci!1047 (merged), !564 (merged), LHCbIntegrationTests!60 (merged)