I routinely empty my pouch if I’m heading into a situation which would make toilet use inconvenient or impossible. There’s no “forcing” or straining involved - it’s just emptying out whatever’s in there, even though the pouch isn’t full.
Passing gas with a pouch is a problem for some of us, and straightforward for others. There’s a third group here that engages in acrobatics or careful body positioning before passing gas. I personally try to avoid it unless I’m on the toilet, but that does mean I need to try to keep gas production down. When it became a real problem for me it was diagnosed as SIBO.