Lo and Behold, an actual gitch
Just to update, there was an actual glitch in the bid production in April whereby some pilots Requests and Preferences were erased inadvertently, (not just mine!) and this has been acknowledged by Rostering.
If you feel that your Requests and Preferences were not honored in Top Bid, I recommend sending a note to Pilot Bid Help to have a look at it. They responded super fast, and were really helpful.
The more people report the problem the better chance it will be resolved at least for the next group, or your next top bid.