As the Pro1 seems to be advancing fine, with "first mass production batch" deliveries starting in the second half of September, I assume the remaining of 2019 will be used for preparing (production optimisations etc.) and producing the second mass production batch.

After that (and if all worked out well), in early 2020, there might be time for considering the next device by F(x)tec.
While it is easy to choose the route Planet Computers has taken, to slightly upgrade the existing design (exterior and interior) with the currently / meanwhile available high-end SoC (e.g. an SDM855 for a "Pro1+"), 1,5 times the RAM (what for?) and double the FLASH memory (again: what for, if the device has an SD-card slot?), I would rather like to see a true "Pro2" being slightly smaller and cheaper, while retaining the same basic design.

If this makes sense for F(x)tec (especially under commercial aspects), please consider Qualcomm's cheapest modern SoCs, which contain "big" cores (i.e., ARM A7x-based ones). Currently the SDM660 would constitute a good candidate. Pair it with 4 GB RAM and 64 GB FLASH memory (more is really superfluous; even 3 GB RAM is fully sufficient, but looks a bit "low-end" nowadays) and a ~ 5,2" display (an even smaller display makes the keyboard too small, when retaining its basic design from the Pro1; it also may be worth considering a classic 16:9 display over a 2:1 one to gain keyboard height) and the result would be the perfect "Pro2" for me.