Temporary non-contract Mobile Broadband with 10GB or more?

I got a line fault on my landline straight away when phone and broadband was activated at my new house on the 31st May. Was told by IDNet that Openreach would be around to fix it within 24-48 hours but 8 days on and still nothing...

So because of this, I've been using a 3GB GiffGaff GigaBag in the meantime and I only have 500MB left now, I can't top it up again for another 3 weeks, that's how it works.

I'm looking for something temporary for the next week or two, and not in a 12, 18 or 24 month contract. Would prefer 10GB or more. Sim card is fine but tethering must be allowed.

I've looked around but most of the mobile networks offer a measly 1GB per month. Any suggestions on what I should do?

Thanks

Get a 2nd GiffGaff SIM?