OpenSprinkler OSBee: reduced hardware?

I am interested in replacing a dozen Pope sprinklers with an OpenSprinkler product.
I have an OS v2, bought two years ago, which I never had time to implement, mainly due to the requirement to lay hundreds of meters of cable for the valves.
I have now seen the OS Bee, which I imagine can be used as an individual timer per station or grouping up to three valves together.
Since putting cables in place is still an issue, I would like to power these by solar panels charging a LiPo battery and powering the OS Bee, and since it can control latching DC valves; all would be good.
WiFi is great, as I could control the OS Bees from openHAB (home automation), which runs already bores, tanks, and other infrastructure on the property.

However, and here my questions (without having read any of the documentation for the OS Bee, sorry):
a) I would not need the OLED display; can I possibly acquire the OS Bee without them? Also do not need the case; will add my own with the solar panel. May need 6-10 OS Bees…
b) Is it possible to reprogram the OS Bees to talk MQTT? The idea is to let them tick (in their time) and simply send them a command like 01-1130-012-06 for valve 1, start 11:30 for 12 minutes every 6 hours. with the OS Bee sending a heart beat every 5 minutes that it is actively watering.

Thanks in advance for any replies.