Honestly, I would strongly advise against this strategy.
I know how time consuming the process is and the amount of time you want to dedicate to it, but the issue will be having a huge gap on your CV. If you get to AC interviews and they see you’re not currently employed after leaving uni, they may question that. If you say you’re spending the year solely focused on applications, I think they’d regard that as a poor use of time management/ability to balance various responsibilities when there will be plenty of others coping with applications, jobs, uni etc.
I also think you’d be incredibly bored and lose motivation. I think spending 4/5 months solid writing applications would be a drag. I think any form of employment/voluntary work is a better option
Have just seen @futuretrainee2023’s comment though and do feel it could probably work with winter schemes. Any grad jobs are competitive these days and if you say you’re actively looking but are also balancing apps, I reckon that’s fine. If you had an AC in March/April though and hadn’t been doing anything bar applications for 8 months, I’m less sure!