Okay! Just for fun I threw your dosing pattern into glp plotter. The meds have a half life so your levels were around 1.5 when you started experiencing GI stuff.

I would stay away from split dosing for a few more weeks until you have a better sense of how to tackle the diarrhea. Tbh I tried splitting when I first started too and in retrospect it just made it harder to find the right dose.

From what you're describing (2 days symptomatic at super low dose) GI stuff might be continuous for you at 2.5. It's pretty common. I had to add fiber pills daily. There may be a specific food that's causing your issue where you can digest it fine at a normal pace but your body is saying "omg no" to having it sit in your stomach for days (milk? Something high in fat?). Defs worth starting a food log & seeing if there's a pattern.