Learn to ignore the pressure readings as a way to check charge. And learn to read and use saturation temps.
That method of thinking in terms of temps instead of pressures was taught to me over 27 years ago by a now-retired boss and mentor. It has served me well on many types of equipment, both high pressure and low pressure. He would say "temps don't change, just pressure". That was before new refrigerants and high efficiency equipment, but the I believe his statement is still valid.