Here is the booking (all in J for 2) for April and May 2020:

YHZ-YUL-YVR-TPE AC/AC/BR Stop

TPE-SGN-SIN-PER BR/SQ/SQ Destination

PER-SIN-IST-WAW SQ/TK/TK Stop

WAW-ZRH-YUL-YHZ LO/LX/AC

This booking cost 320K points and $576 fees and surcharges (carrier surcharge $50) plus $69 booking fee.

Australia Passenger Move Charge $54.00
Canada Domestic/International Air Travel Security Charge $25.91
Swiss Passenger Security and Noise Charge $21.70
Singapore Airport Development Levy $5.80
Poland Passenger Service Charge $0.30
Canada Harmonized Sales Tax $4.20
Singapore Passenger Service and Security Fee $11.60
Canada Domestic/International Airport Improvement Fee $28.00
Turkey International Airport Service Charge $7.40
Taiwan Airport Service Charge $21.20
Australia Domestic/International Safety & Security Tax $5.90
Australia International Service Charge $32.20
Poland Domestic&International Airport Tax $20.30

Carrier Surcharge $49.90

Total per passenger $288.41

Total passengers $576.82

Booked YYZ-YVR-TPE-YVR-YYZ a few months ago, all in J but last YVR-YYZ segment. J opened up yesterday so I called in. Just got my itinerary/receipt and received a $24.80 refund on taxes, fees and surcharges. Nice! I guess the surcharge went down since I booked. I would have expected them to go up moving from Y to J.

YYZ-TPE (BR 777 - J)
TPE-ICN (TG 777 - J)
ICN-NRT (OZ 321 - J) - Stop
NRT-BKK (TG 380 - Y) - Stop
BKK-SIN (SQ 787 - J)
SIN-DPS (SQ 787 - J) - Destination
DPS-SIN (SQ 333 - J) - 23 hour layover
SIN-IST (TK 777 - J)
IST-BOS (TK 333 - J)
BOS-YYZ (AC 190 - Y)

$271.26 in taxes plus booking fee. 155k points.

All J

YWG-YUL AC
YUL-ZRH LX 330
ZRH-CPH LX

CPH-PEK SK 340
PEK-SIN CA787
SIN-PER SQ 787

PER-SIN SQ 787
SIN-TPE BR 777

TPE-ORD BR 777
ORD-YYZ AC
YYZ-YWG AC

$400.28 Fees. Call in charge $31.50

Called in to book the following for my wife and I for March 2020:

VIE - IST TK J
IST - BKK TK J
BKK - TPE BR Y

$75.60 fees; no call-in charge (from what I can see), perhaps as I mentioned to CSR that this routing is valid and should have been shown instead of the multitude of Air China / Austrian choices.
I will definitely be looking later to see if VIE - TPE on BR 787 J will open up!

A friend has the following J itinerary:
YVR-HND NH
HND-KUL NH
KUL-SIN SQ
SIN-JNB SQ
JNB-WDH SA
WDH-JNB SA
JNB-SIN SQ
SIN-HND NH
HND-YVR NH