You can stay in India for an extended period while your Form I-485 is pending, especially if you have a valid Advance Parole document and Employment Authorization Document (EAD) for five years. However, maintaining continuity in your job is crucial. If you're still working remotely for the same employer or a different one under the same or similar job, there shouldn't be significant issues.

Quitting your job may raise questions about your green card eligibility. However, if you obtain a job offer from another company, filing a supplement J to demonstrate job continuity is advisable. This ensures that you can re-enter the US smoothly using your Advance Parole upon green card approval.

You can return to India to work for the same employer for multiple years and then come back to the US. You can also convert your case to consular processing if needed, provided there's continuity in your job. As long as your Advance Parole is valid, there shouldn't be any significant impact on your pending Form I-485 until your priority dates become current.

Yes, you can work for a company based in India while on an H-4 visa, especially if you have an Employment Authorization Document (EAD). Working remotely for a foreign company from within the United States is legally permissible. However, it's essential to consider tax implications. You may be required to pay taxes in the USA, so it's advisable to consult with a tax professional or accountant to understand your tax obligations accurately.