Not sure which option — Standard, Plus or Registered — suits your use case?
The choice depends on the proof you require:
ePost Standard: You just want to know that the message has been delivered.
ePost Plus: You want to know if the recipient has opened the letter.
ePost Registered: You need legally binding proof of delivery — for example, for a termination or reminder.
ePost Plus and ePost Registered are especially suitable for deadlines. They improve your evidential position and provide transparency about whether your recipients have already received the letter.