Many of T-Mobile’s leases are managed by tower companies such as Crown Castle. In this situation, Crown Castle would act as the tower manager and negotiate cell tower lease extensions on behalf of T-Mobile. Any changes to the lease terms outside of pre-approved language would require Crown Castle to seek approval from T-Mobile on those changes. These arrangements are not uncommon in the industry as wireless carriers focus more on the engineering and marketing than tower building or lease management.
It is important that your cell tower lease consultant understands the outer limits on what the tower is worth to T-Mobile in cell coverage and traffic capacity to determine the important terms that must be negotiated in your lease.