Yes, under the CISG Advisory Council opinion, ‘oral’ can include an electronically transmitted sound and notice can include email; this provides that the offeree has consented to receiving messages in this way.

For Article 21(1), the assumption is that despite a delay, the acceptance can be valid if the offeror confirms without delay.

For Article 19(2), slight deviations automatically constitute an acceptance without additional consent from the offeror. To the contrary, the offeror must object if it does not agree to the deviations.

The difference is noteworthy, because a delay could have significantly less impact on the offeror than amendments to its offer, yet, the onus to object lies on the offeror under Article 19(2). 

The offeree will often not be in a position to ascertain that its acceptance has arrived late and therefore is in a weaker position, with the consequence that the obligation is then on the offeror to communicate if it does not accept the late acceptance.

If technical problems cause delay on either the offeree’s or the offeror’s server. If an acceptance lands in the spam filter, it may not be read in time. 

A notice of acceptance is not dispatched until it has left the offeree’s server. Consequently, if the notice gets stuck before leaving the offeree’s server, this is the responsibility of the offeree. According to the ICC eTerms, an electronic message is dispatched when it enters an information system outside the control of the sender. There is thus a definitional—if not practical—disparity in the understanding of ‘dispatch’ in the context of electronic communications.