Pretty surprised MAG ALPA didn't use the check-in requirement in the contract to force a TA
If the MEC had played hardball instead of Mr. Nice Guy, and told all of your pilots to start complying with the contractual requirement to check-in, under 117 there would've been a complete meltdown and the company would've been forced to the table--no TA, no modifications to the check-in provision.
Another example of who their priority is... or isn't...