I would recommend contacting SAAS or the relevant Student Finance branch for RUK to look into the finance side of things to ensure you will be funded for the full course. Going from second year in one uni to second year in another may present challenges in terms of funding entitlements. Also on a logistical level, it's really not advisable normally to plan to do external qualifications while at uni. As you have absolutely no mechanism to resolve any exam clashes and so if you have one then you are missing one exam or another which will invariably lead to a fail in that module/qualification.
In terms of admissions realistically I would suggest you contact Strathclyde first directly to find out what their expectations would be. Depending on your current degree subject they may accept that in lieu of specific advanced highers for example. They may or may not accept students from other degrees for the advanced entry as well. In terms of predicted grades etc, assuming they do accept people from this situation and it's not a financial impossibility and you don't have any exam clashes making it a moot point, they may well just consider your application on its merits and make you a standard conditional offer and you would need to achieve that. This is something you can ask them when you contact them as above though.
However I think overall this is a challenging option and may not be practical in many situations. Also depending on what your longer term goals are, may be wholly unnecessary - if for example your goal is to work in the computing sector and gain a relevant degree to do so, a degree apprenticeship is invariably your best option as that's most directly aligned with what the sector is seeking in terms of qualifications and experience. It also sidesteps a lot of the issues you face applying to a degree elsewhere in this situation (e.g. funding, admissions requirements, etc). You may also find that your current degree is a suitable first course and you could well either go directly into such roles or do a more specifically computing focused masters degree, depending on your current subject.