I've checked this with 2 devices 150LMT and 2699LMT-D and 0 byte remove subscription from:
- subscription list in user menu
- subscription count and position in debug -> Developer Info -> Traffic -> Traffic Receiver Subscriptions
Be aware of few things - if you have quite new receiver and have TrafficProvider.xml file device can recover subs (I don't know procedure). Try this with licence not sold with receiver you can also remove apriopriate key from TrafficProvider.xml. Strange things are going when you remove one sub from multi-sub (i.e. Medimobile Nordics (FI, NO, SE, PL). Sub hang in user menu, sub is removed from subs in debug menu - receiver can not tune signal.