Our sources told us multiple times the Sony A7IV was scheduled to be announced in September with shipment start in October. But as you all know by now there is a worldwide chip production shortage. The ZV-E10 launch was postponed for two months because of this (from End of May to July first…and now to August). And also other camera companies had to delay the mass production of new cameras. While chip makers are doing everything they can to increase the production the supply issue will be solved by early 2022 only
At this stage I don’t know if Sony will stick to the September announcement and eventually only postpone the shipment start from October to November/December or if Sony somehow found a way to get around the issue.
As for the A7IV specs I still have no 100% solid info but it appears the camera might use a new 30MP (or 32MP) sensor. It will also NOT record 8K.