I find it hard to believe it but the source who shared this is actually a good one. So unless he got intentionally mislead by Panasonic this could really happen. he reports:
Panasonic is working on a GH5 high speed burst mode. It will also offer up to 20 frames/s in RAW!
It should be added via future firmware update. this would match the current performance of the new Sony A9.
For sources: Sources can send me anonymous info at firstname.lastname@example.org (create a fake gmail account) or via contact form you see on the right sidebar. Thanks!
To get notified on all upcoming news and rumors be sure to subscribe on 43rumors here:
RSS feed: https://www.43rumors.com/feed/
Rumors classification explained (FT= FourThirds):
FT1=1-20% chance the rumor is correct
FT2=21-40% chance the rumor is correct
FT3=41-60% chance the rumor is correct
FT4=61-80% chance the rumor is correct
FT5=81-99% chance the rumor is correct