There are no givens when it come to the definition of a category. Its entirely up to Bloch. One possible category could be "turbojet + Q400". In that case, with a ratioed sorting, the outcome for the first seniority block would be 650 PCL, 300 Mesaba and 150 Colgan (these are approximate numbers). So the rough ordering would be a repeating cycle of 4 PCL CAs, 2 MSA CAs and 1 CJC CA. With this category placed first the likely second block would be SF34 CA where 150 Mesaba would be ratio integrated with about 150 Colgan. A repeating cycle of of 1 Mesaba and 1 Colgan. Then the FO status of both of these blocks would be added in behind.
There is no magic in "status and category" and its almost universally used in arbitrated pilot seniority list integrations.
I understand that it CAN be done. It just doesn't seem logical at all. At least give a guy some type of credit for when he was hired. I guess we will see. Is that party still on at Murphs? After this last couple weeks we are going to need it more than ever.