So after over 2 years I finally hit a plateu

Current stats: 5'10" 205 lbs 11-12%bf

Trying to get out of this funk I am in for the past 2 months my measurments keep fluctuating quarter of an inch up and down every week weight continuing to stay at 205. Calories up well above maintenance protein intake up.

Current supplements:
A-AKG
Serious Mass (gainer)
Creatine Mono
Test Force (natty test booster)
Engorge Appetite Stimulant

After coming off my Havoc/MaxLMG cycle 2 months ago I was able to keep all the weight achieved with no spike in BF% but since then I have not been able to put on any weight not even fat no matter how hard I work or how much I eat. Its like my metabolism is working double time.

So decided to switch up my split do to me thinking this might be cause by muscle memory. So feel free to suggest anything I should do including my routine below to get out of this funk. My next step if this doesnt work is pinning. Started this split 2 weeks ago and honestly I stay more full and vascular do to the constant pump I have from working this hard.

3 day split 6 days on 1 day off

Day 1 Chest/Bis/Forearms
Day 2 Shoulders/Tris/Calves/traps
Day 3 Legs/back/calves/traps
Day 4 Chest/Bis/Forearms
Day 5 Shoulders/Tris/Calves/traps
Day 6 Legs/back/calves/traps
Day 7 off

Abs thrown in a few days during the week usually when i feel like it

Day 1 and 4:
Chest Day1
Incline Bench 4x6-10
Bench 4x6-10
Isolated Wide Chest 4x6-10
Dumbbell pull over 4x6-10
Cable Flys4x6-10
Chest day 4
Incline DB press4x6-10
Dumbell Press4x6-10
Dips4x10
Isolated Incline4x6-10
Isolated Bench4x6-10

Biceps day 1 and day 4
EZ bar curl 4x8-10
Preacher curls4x8-10
Incline DB Curls4x8-10
Hammer Curls4x8-10
Cable Bar Curls4x8-10
DB curl4x8-10

Forearms day 1 and 4
Barbell Wrist Curls 6x15-20
DB wrist curls6x15-20

Day 2 and 5
Shoulders day 2and 5
DB Shoulder press 3x6-10
Front DB raises3x6-10
Latteral Raises3x6-10
Plate Raises3x10
Upright rows3x10
Some machines usually added in at the end

Triceps day 2 and 5
Dips 3x8-10
Close Grip bench3x8-10
Lying BB extension3x8-10
Skull crusher3x8-10
Cable pull downs3x10
Pushdowns3x8-10

Traps day 2 and 5
DB shrugs 4x20
BB Shrugs 4x20

Calves day 2 and 5
Calf raises 4x20
Seated calf raises4x20

Day 3 and 6
Back day 3 and 6
Pull downs4x6-10
Cable Rows4x6-10
BB rows 4x6-10
T-Bar rows4x6-10
DB rows4x6-10
Deadlifts4x4-8

Legs day 3 and 6
Squats 4x8-10
Leg press 4x8-10
Leg extension 4x8-10
Leg Curls 4x8-10

Calves day 3 and 6
Seated calf raises4x15-20
Calf raises 4x15-20

Traps day 3 and 6
DB shrugs 2x20