I94 Dates

[WhoDaDaddy]

Question in relation to dates attached to an I94 record. I understand that the I 94 is now an electronic record now so there isn't anything physical given to passengers anymore so not sure how easy it is to know the dates officers put on the records.
My question is the following scenario. If I enter the US from the UK on a B2 visa and am granted leave to remain for 6 months, can the date be shortened if I leave the US for a few days. My visa is multiple entry and I will need to go to Mexico for some short trips.

Can the POE officer change the date I have to leave the US to a time that is earlier than the date I may originally be given (6months) when I first entered the US?

Hope what I'm asking is quite clear.
Thanks in advance.

[ramabalaji]

Instead of stamping on the I 94 card as done earlier, now a days the IO stamps the I 94 validity date in the passport at POE. This was done to me when I entered Dallas on 12 May 2015. Please check your passport.

[rockyrajv]

I think they don't change ur I-94 duration for a trip to Mexico if you are in US as a visitor/biz professional

I-94 number is visible at https://i94.cbp.dhs.gov/I94/consent.html