I think you are on de-facto contract too. The fact the probationary period was not confirmed in writing is not critical. The contract you quoted has no clause for extension of the probationary period (some do), and thus because you are still there and they have been paying you, both parties must have accepted you have gone on to standard terms.
Yes, the govt will still provide pay if an employer is insolvent and unable.
https://www.gov.uk/your-rights-if-your- ... -insolvent Both for pay and redundancy pay. Although claiming such can be a long and tedious process.
Incidentally, your employer IS technically insolvent. As soon as they are unable to pay any liability on time this is true. You could petition for them to be wound up. Although it would be pretty self-defeating, as then you wouldn't have a job.
The employer is also liable for incidental costs which any employees incur due to late payment. Overdraft or bounced payment fees for example. They should have offered. They will certainly lose if taken to court by any employees for such costs. Make sure your fellow employees know this, even if it doesn't affect you.
Leaving without notice: In theory, an employer could sue an employee for liabilities incurred by them in covering the work. In practice, I've never heard of this happening. And as they are already in technical breach of contract, in your case they'd lose anyway.
I've walked out of a company on short notice too. I was in-between projects and not very busy when offered another job. First I asked if I could leave that Friday, but no manager was willing to commit to the decision "I can't authorise that" they all said, so I turned it round and said "I
am finishing on Friday. Tell me if that's a problem." They didn't, so I left.
It is also worth
asking whether they want you to honour your notice period. If they're truly skint, they might be quite happy for you to leave at very short notice to reduce the payroll. You can always terminate any contract by mutual agreement.
Gryff