For the moment, no official reason has been given.
The updated Model S was revealed last month.
Some buyers have been waiting for months for their car.
The only thing Model S buyers are being told by Tesla is that there currently is a “hold” on deliveries. Speculations as to why this is happening vary quite a bit.
One hypothesis is that this may be related to the Model S Plaid that caught fire shortly after being delivered late last month. Musk had explained that the Plaid was delayed in order to make sure that the new battery pack was safe…
One semi-official explanation was given by a Tesla Center. The cause for the delivery delays is related to a new more thorough inspection process which takes longer to complete. Even so, Tesla is not giving hopeful soon-to-be-owners a new handover date.
Electrek reports that, based on buyers, the holds began last weekend. Some of these buyers have been waiting for months to get their new car and have received confirmation that their Model S is at the Tesla center – they just can’t come and get it yet.
Another possible reason for the situation could include a required software update for any of the onboard features and technologies including the UI.