eplc. Charlie Brown - Am I Underwatering?

[Ginger9899]

Hello, I purchased this bag baby eplc Charlie Brown last fall and repotted it into a common bark/charcoal/perlite mix. I did soak the bark overnight before I potted. It has been on the edge of a screened west facing porch and gets about 4-6 hours of direct afternoon sun every non-cloudy day. I think I may have overpotted it, and I realize the new lead is on the side and not towards the empty middle, but I had advice not to bother it now since the new lead started.

My question is, the two pseudobulbs previous to the new growing one were fat and smooth and plump before the new one started growing, and now they are quite shriveled. I water it with rain water, a 10 minute soaking once a week, and water by running water through pot at least once in middle of week. I have skipped this occasionally if I see moisture in the pot but mostly it is bone dry and light as a feather the same night I water it. The weather here is super super hot now, I wonder if I am not watering enough, or if the shriveling is to be expected since the roots weren't real established from when I purchased it.

I am afraid to water more though....don't want to rot anything! Thanks for any observations and advice you may be able to give.

*edited to add I just watered this morning, looks and feels really dry already!