Hi @AJ Singh
Thank you for reaching out.
As far as I know, the Microsoft 365 Developer Subscription (E5) benefit is only available to subscribers who hold a Visual Studio Professional (Standard) or Visual Studio Enterprise (Standard) subscription. This benefit is not included with Visual Studio cloud subscriptions, such as Visual Studio Professional Monthly or Visual Studio Enterprise Monthly. Therefore, the Microsoft 365 Developer Subscription (E5) tile will not appear in the Benefits portal for users with a Professional Monthly subscription.

You can refer via: Join the Microsoft 365 Developer Program with a Visual Studio Professional or Enterprise subscripti…
Regarding subscription pricing, you can review the details here: Purchase Visual Studio cloud subscriptions - Visual Studio Subscription | Microsoft Learn. Please note that pricing may vary depending on the purchasing channel, region, and licensing program. We recommend reviewing the official pricing information and consulting your preferred reseller or licensing provider before making a purchase decision.
With respect to changing your subscription from Visual Studio Professional Monthly to Visual Studio Professional Standard or Visual Studio Enterprise Standard, there is currently no documented self-service conversion process. Standard subscriptions are typically purchased through licensing channels such as Volume Licensing, Retail, CSP, or other eligible programs. In most cases, you would need to purchase the desired Standard subscription separately and have it assigned to your account.
For assistance with subscription purchases, licensing options, upgrades, or billing questions specific to your scenario, I would recommend contacting Visual Studio Subscription Support for further assistance.
You can reach out to them via: Activate Microsoft 365 developer subscriptions - Visual Studio Subscription | Microsoft Learn
I hope this helps.
If you have any additional concerns, feel free to comment below. I would be more than happy to assist.
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