Manual lymphatic drainage while on chemo concerns or not?

Mymamma

my mom had a partial mastectomy in April with 16 nodes removed-9 positive....ugghhh. This was complicated by saroma and needing drains reinserted . Also margins were not clear. So she had her first ac cycle last Friday and the plan is ac-t for 8 cycles total then full mastectomy. She has been complaining of heaviness and rubbing in her upper arm and our lymphedema clinic cannot get her in until July 31. I called and scheduled an appointment with a manual lymphatic drainage specialist and her MO is fine with this however I just read that you should not have MLD on chemo and there were even concerns from some voices about MLD leading to Mets. Any thoughts or hearing the same and or contradicting info