Is this normal for the SHBG to drop like this?

[fastman9]

I started TRT around two years ago. The first year wasn’t good, but a start. The Doc started me on 200mg of Test Cyp per month. I didn’t like this as I had mood swings, etc. With follow up tests and still low and dropping T levels the Doc upped the protocol to every two weeks. I felt better but not great. About six months later more texts and way low T levels (210), the Doc upper my protocol to 300mg every 2 weeks.
I waited 3 cycles, seven weeks and got tested again and had a large swing in Total T levels but a drop in SHBG.
So my question is this normal for the SHBG to drop like this?

I’m 52, 175-180, 6-1, lean with mostly cardio work outs (Boxing and Jiu Jitsu) 3 times a week.

All other BW and such came back in normal ranges.

• Standard range 3/25/13 5/6/14 5/6/14 8/26/14 12/18/14 3/19/15
• SEXHORMONE BINDING GLOBULIN
• 11 - 78 nmol/L 29 27 26 18 Yes, twice the tests where not run.
• TESTOSTERONE, TOTAL
• 221 - 716 ng/dL 341.1 326 316 322 210 924

Sorry, I could not get the spacing good here?