Hi @LM-5132
Thank you for Reaching Out Microsoft Q&A Platform.
I understand that you have some queries regarding the use of E3, E5, and P2 licenses in your GCC High environment, along with concerns about any limitations, security considerations, and the differences between E and G licenses.
Based on the information provided, here's the difference between E and G licenses: E licenses (such as E3 and E5) are designed for commercial use and general business purposes. In contrast, G licenses are specifically intended for government offerings, such as GCC High and DoD, to meet the unique security standards and regulatory requirements of government entities.
For additional information about Licenses refer these documents: https://www.microsoft.com/en-us/microsoft-365/enterprise/government-plans-and-pricing
https://www.microsoft.com/en-us/microsoft-365/enterprise/microsoft365-plans-and-pricing
For information on the limitations or security concerns associated with using E3 and E5 licenses in GCC High, please refer to this document: https://learn.microsoft.com/en-us/office365/servicedescriptions/office-365-platform-service-description/office-365-us-government/gcc-high-and-dod#compliance
The comparison between E and G licenses reveals that they offer different environments, which can vary based on the specific requirements and regulations of each cloud environment. The existence of both E and G licenses serves the distinct needs of commercial and government entities.
For Additional Information refer this document: https://learn.microsoft.com/en-us/office365/servicedescriptions/office-365-platform-service-description/office-365-us-government/microsoft-365-government-how-to-buy#what-makes-microsoft-365-government-different-from-microsoft-365-for-enterprise-offerings
Do let us know if you any further queries.