Hello, a new newbie hoping to get some guidance.

I own a 7-month old Lelit Anna (PL41TEM). I recently noticed that the water flow from the group head was noticeably slow. The water flow through the group head with no portafilter was ~120mL/min. The water flow through my steam wand was ~500mL/min. The machine has no problem reaching over 9 bar with blind basket on, so I think the pump is fine. I also removed the water softener filter to make sure that wasn't the issue. I also cleaned the shower screen.

I live in an area with fairly hard water (~200ppm). Since I haven't replace my water softener filter for the last 7 months, I thought to try descaling the machine. (I did recharge the water softener every 2-4 weeks, and I just ordered new set of water softener filter!). After descaling with Dezcal for 10 minutes, my group head water flow rate has gone up to ~250mL/min.

So three questions:
1) Does 250mL/min fall in the normal range for Lelit Anna?
2) Is it a bad idea to try descaling one more time?
3) Should I try to disassemble the machine to clean out specific parts (e.g., solenoid valve)?

Thank you in advance for your input!