GSTR-1 Export Invoice - Partial Payment Query

Holla, need quick clarification on GSTR-1 filing for export under LUT:

Situation:

• Invoice: $907 USD (June 26, 2025)
• Received: Only $500 USD (July 10, 2025)
• Outstanding: $407 USD (client financial issues)

My Action: Filed GSTR-1 for June with ₹42,876 (converted $500 at June 26 rate) in Table 6A

Questions:

1. Correct to report only received amount vs full invoice value?
2. If remaining $407 received later - how to fill the supplementary GSTR-1 for that month?
3. If it becomes bad debt - any special GST treatment needed?

Export under LUT, all documentation proper.

Thanks!