There is an official statement from GameStop regarding the €99 PS4 Pro trade-in promotion. The offer is definitely intended to continue.
GameStop will provide an update on the situation on April 26. It is a press release regarding the current PS4 Pro trade-in promotion at GameStop.
GameStop speaks of explosive demand and massive shortages
We are copying the press release verbatim:
(Memmingen, April 26, 2017) – Due to the explosive demand and the enormous response to the current GameStop trade-in promotion for the PS4 Pro, there have unfortunately been massive shortages in the stores. GameStop is therefore currently unable to fulfill all trade-in requests. However, there are and have been several restocks planned for the entire promotional period, some of which are already on the way to the stores, to quickly restore access to the promotion for all customers.
GameStop asks all customers for some patience and regrets the delays.
The trade-in promotion for the PlayStation 4 Pro console remains valid until May 14, 2017, in all GameStop stores in Germany, Austria, and Switzerland, and only while supplies last.
The press release ends with a link to the promotional page of GameStop.
Damage control seems necessary
We reported on the offer that is being referred to here on Sunday evening. GameStop offered that players could trade in their old PS4 along with 2 games and €99 for a new PS4 Pro starting Wednesday.
The offer led to the aforementioned supply shortages in the following days. This is probably also because reservations and pre-orders had already been accepted beforehand. Therefore, the offer was sold out in some places by Monday and Tuesday.

Today, at the actual start of the promotion, many buyers went to the stores but were turned away, resulting in a so-called shitstorm. People vented their frustrations on social media outlets like Facebook or Twitter, making serious accusations against GameStop. There were talks of nepotism and bait-and-switch offers.
The term “dirty store” was repeatedly mentioned.
A journalist from the largest German-speaking PC site GameStar was denied access to a GameStop store.
What do you think about GameStop’s statement? Does it reassure you, or do you want to try your luck again in the coming days?