A few things.... If your husband finds work, you can apply for your RC cards online and use the European passport return service. EDIT: WE [You] would do the application online, then print it and either take it down to Rutherglen or over to Edinburgh (you have to make an appointment), pay a small fee, and they'll photocopy and return your passports to you on the spot. They'll then mail the rest of the packet on to the HO people. Apparently it's no quicker than using the paper form, but the online form is a lot less murdered trees.
And you get your passports back the same day. You ~can't~ use the online option or passport return service if your husband is applying as "self-sufficient" or if he does not apply (he's not required to) and you apply without him. You'll have to send all your passports (including his even if he doesn't apply) to Durham with your printed material and original documents proving your status, etc., including a summary of your CSI benefits. I sent in the whole darned insurance booklet (all 96 pages of what is/isn't covered) from my ex-employer when I sent in our materials in July, to be safe, and the Vitality Health booklet for my daughter.
Best intentions aside, our packet wasn't opened/logged in until about six (or 7) weeks later. Supposedly once your materials are logged in you can request your passports back, so if you have to do the Self-sufficient application route, plan to not see those passports for a couple of months at the very best. I'm told that once you're in the system and request them back, you're supposed to get them within ten days. I made three inquiries and never got a response until they sent our entire packet back, so I can't vouch that they'll return them in those ten days, as advertised.
I am waiting to see how a job interview goes. If I am hired to start in the next few weeks, I intend to use the online option. If it's either not going to be immediate or I don't get hired, I'm going to resubmit using the "send everything as hardcopy to Durham" option. AND, I will pay for it with a postal money order or a check this time. We got our whole packet returned after about 8 weeks of no communications because they said the credit card info was bad. We're hearing from various creditable sources that that happens a lot more than it should, and has (like in our case) happened even though the information provided was correct. (Our bank said no attempt had been made to run the card through, as far as they could tell.)
So, unless they've added a lot more bodies to be processing these, or unless the number of applications to Durham has dropped, if I send in our RC aps based on me being Self-sufficient by, say, Oct 15, I don't expect to even have a registration number until mid-December at the earliest. And if I immediately request the passports back, I don't expect we will see them until the end of January, if we're lucky.
If you have to do the same - Self-sufficient application to Durham, be
absolutely sure to send it via a method that has tracking. (The Royal Mail has proven to be pretty good.) And don't forget to include as the value both the cost of shipping and what you'd have to pay to get all the passports (and other docs in the packet) replaced urgently when you are given the option to insure it.
Oh. And on the part-time job. I could have it wrong, but it's my understanding that any work, as long as it is "genuine and effective" counts as "worker". It doesn't have to be full-time. Again, unless I've got it wrong, the HMRC primary threshold for paying NI is £153 per week. So, about £7.50 per hour for a minimum of 20 hours meets the threshold. (Based on 2015 figures - can't find anything more recent).
https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2014-to-2015#class-1-national-insurance-thresholds