Poland

Sender ID: 

Alpha Sender ID are supported.

All numeric senders will be overwritten by "SMS" to ensure delivery.

Sender IDs that contain the operator name (ie, "Orange", "Play" etc) and sensitive Sender IDs (such as "Police") will be blocked completely.

A2P

Messages with ads of Premium Rate services in content will be rejected

Messages that contain premium numbers and shortcodes in the body of the message will be blocked as messages related to Premium Services are not allowed to be to sent via A2P connections.

Gambling

Messages with betting odds will be rejected

Concatenated messages

Concatenated/long messages are supported. 

Other features/restrictions of note:

Delivery Receipts:
Handset delivery receipts are supported.