Moving from GCSEs in England to Scottish Nat 5 - nightmare?

[EducationMoveQuestion]

Question for folk with secondary education experience both sides of the border: Would an academically-average 15-y-o leaving England after one year of GCSE study (no exams yet taken) & entering a Scottish high school at the start of S4/start of Nat 5 year cope/adapt ok? If relevant, she started reception aged 4 years 4 months but wouldn't have started P1 until 5 years 3 months so has an extra year of schooling under her belt compared to the potential cohort.

I'd have thought that academically she'll be ahead since she's done one year of GCSE, so it shouldn't be a problem. The only worry would be if she'd get the options she wants as Scottish schools start the next year at approximately the start of June and do about 4 weeks of the Nat 5 course in S3 before the summer holidays so classes may be full.

I know that technically Nat 5s are a one year course, but in practice ours have started content much much sooner, so it depends on if there’s stuff that’s been missed. You’d be unlucky if it was significant for all subjects.
I think you’d want to check for maths what concepts had been covered so far. Also English technique is particular so be prepared to work on that (RUAE) unless it’s done in England too.

I don’t think the extra year of schooling will make a real difference.