Just after I'd left, cursing myself for having gone on a wild goose chase, my phone rang. My co-workers (former co-workers) had spotted C. coming in, and had asked him to wait for me in the car park. I met him there and he asked me "Hedwig, what's this I hear? How have you been sacked? Tell me!" So I did.
One thing you should know about our CEO: he prides himself on having created an atmosphere in which people feel safe, secure, and happy, almost as if we were a family, so instead of bitching about The Biatch, I just told him how much I'd enjoyed working there [and I have], how disappointed I was in my dismissal with just a few days' notice, and was this the way a family that truly cares for its members would behave? He agreed with me that it certainly didn't sound like it, and promised to look into it. Of course he said the Board doesn't usually interfere with a manager's powers of hiring and firing, and I told him I wasn't expecting him to, to which he repeated "usually". Anyway, he couldn't make me any other promise than that he would look into the matter, have a word with HR and The Biatch, and then get back to me. So we'll see what happens next.
Meanwhile, it's back to the hairdresser's to get the magenta out of my hair. If I'm going to have to apply for jobs again, I'd better not look like a freak.
ETA: I've just gotten off the phone with C. He let me know that after speaking to The Biatch and HR, and concluding that it would be pointless to try to reverse the decision as their position, as he explained, had already become entrenched; he had personally authorised the pay out of 3 months' salary to my account by way of a sort of severance pay. He said he was very sorry things had gone the way they had, that he admired my pluck, and that I could always cite him as a reference. He's even given me his mobile number and asked me to stay in touch, let him know of any problem I might have.
So, I am still fired. But at least, I don't have to worry where my next meal is going to come from.