T5 web forms invalid trust number

I’m using CRA’s web forms to submit T5 slips & summaries. T5 is from operating company to trust.
Last year, a trust was code 1, individuals. This year, they’re code 4, association. Used same procedure as in the past. Went through RAC, enter BN, go down to RZ section, choose 2019 T5, start original using prior year submission info, enter all info on screen. Go to validate and get the error message that the ID number is either missing or incorrect. Only way to proceed is to enter T00000000 as trust number. Used their help - contact option and was called back really fast. CRA rep had a web forms demo in front of her, but no answers. Transferred to business windows and was disconnected. Submitted T5 without trust number. Anyone else run into this? Poor time for system glitches.

The code for a trust has always been 4. (At least back to 2012)
You’ll need to NOT use the prior year submission to start.

Why are you using the webforms instead of Taxcycle? Much easier and warnings about any glitches before you are online trying to file it.