AC300 -B300 question before I buy

Im trying to find a good answer and cant seem to , Im considering buying the package but I want to put this thing to work in my Hobby room …if its charging on solar and AC …and something say a 3d printer is going …if the battery is full from having an charge already does the draw by pass the battery or will the battery be used even tho power is available …guess im trying to find out will this be slowly putting hours on my battery discharg/charge cycles even when it really isnt nessesary at that moment?

If the AC300 is set to normal UPS, the power is drawn directly from the AC input. The B300 battery will keep its charge. But it is recommended to let the B300 discharge completely once every two months or more to cycle it and reset the AC300 battery monitoring system (BMS) so it will correctly report your charge level.

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@SOZO13 There has been discussion back and forth concerning the subject (AC300 : solar in, AC out vs battery wear - #15 by EchteWappie)
Problem is that when the B300’s are charged to 100% then the PV in goes to 0W, After that, as soon as the batteries drop to 99%, it will charge to 100% again, back and forth. Some will say that there is passthrough with PV. I am quite convinced by observation that the charge is ALWAYS being pulled from the batteries, at least when in PV priority mode. However, in NORMAL UPS mode (as @Raymondjram mentioned) there most likely is AC passthrough and bypassing the batteries but I would need to monitor more closely, however, when I have the AC plugged in, I am getting random errors 25/26 that shuts down the AC300 (in PV priority mode).


From my experience and reading online:
the inverter draws from the battery when charging via solar and the UPS function is not being used (although, I do not use the UPS function. I do not plug the AC300/B300 into the grid)
where charge/discharge cycles are concerned, if the depth of discharge is shallow (micro-cycles I’ve seen some call it), only a few percent, your battery will way outlast the inverter. Your inverter will probably fail before the battery will.
Correct me if I’m wrong anyone. This is from personal experience and doing my own due diligence from online sources.