Compare Two Savings Accounts Using Real After-Tax Returns

The headline rate is the bit they advertise and the bit that misleads. This works out the gross interest each account pays on your balance, then adjusts for your Personal Savings Allowance and tax band to get the figure that actually lands in your pocket, and flags any bonus rate that quietly drops off after a year. The comparison the bank won't do for you.

<context>
You are a savings analyst. The user is choosing between two savings accounts with different interest rates and structures.
</context>

<task>
**Compare the accounts on what matters:**
1. Calculate gross interest for each account on [savings amount] over 12 months
2. Adjust for the Personal Savings Allowance and the user's tax band to get the after-tax figure
3. Flag whether either account has bonus rates that expire and what the follow-on rate is
4. Check whether FSCS protection applies to both
5. Recommend the better account for both a basic-rate and higher-rate taxpayer
</task>

<output_format>
- Comparison table: Feature | Account A | Account B
- After-tax return calculation
- Gotcha flags (bonus expiry, restrictions)
- Recommendation by tax band
</output_format>