It seems bminer gives more invalid/stale shares than other miners. Counting the ones you got so far (orange bars in FLypool), i see 96 invalid shares (normalized) for bminer, and 16 for dstm.
Yes, that has been a persistent "feature" of bminer for several releases now.
What's the exact % of invalid shares, I wonder... I too thought that bminer has quite high percentage of rejected shares until I switcher over from Nicehash to miningpoolhub and suprnova (haven't tested new release on flypool yet). Surprisingly, on NH I had 1.5-2.5% of rejected shares, but on MPH and suprnova I now have 0.4-0.3%, with the same setup and OC (that's 2-day statistics). So looks like rejected share rate varies from pool to pool.