Can anyone else make sense of this enhanced maternity pay policy?

[WhereverElse2019]

Hi all. This is the maternity pay offered by the company I work for (copied from handbook):

Weeks 1 - 6 : We will top up SMP/SAP/MA/Adoption support to 100% of your Company Average Weely Salary (CAWS)

Weeks 7 - 15: SMP/SAP/MA/Adoption Support as well as 100% of your CAWS

Weeks 16 - 21: We will top up your SMP/SAP/MA/Adoption Support to your CAWS.

Weeks 22 - 39: SMP/SAP only

Am I right in thinking this is basically full pay for 21 weeks? Weeks 16 - 21 make it sound like they offer full pay on top of SMP but that can't be right surely? Not sure if I'm simply not reading it correctly? I'm not currently pregnant or TTC but am thinking of starting next year.

Thanks!

These posts:

Do feel free to prove me wrong. Which employers are paying SMP one top of full pay? I’ll wait.

Wait as long as you like. You said "you can't get paid more than full pay". You can. Very simple. You can. Because the pay in may leave is based on a reference period and if you earned more during that period (for example had a bonus or worked a lot of overtime) then that would increase your pay while on leave and might even take you over 100% if your employer only pays the 90%. Of course, if they enhance their policy may well say they enhance to 100% maximum. But it might not.

I'm not listing the employers, because it's every employer.