Yeah, I remember those. You could get a month of pay for each year of service up to 12 months plus 2 months on top (14 total.) You needed to be 50 years old and 15 years of service. If I recall your DPSP and RP funds where either frozen or transferred to you. I don't recall what happened with healthcare. I think it was as if you met the 55 year age and could get it at a discount unless you had 30 years then it was free (until HP started passing on any increases to the retiree.)
It was a good deal for some but being unemployed at 50 even back then could be precarious.
No telling what HPE or HPQ might offer for early retirement today. I think they dumped enough people that an EER isn't really needed any more.
They did a ramp down (phased) type if EER several years back but it wasn't a good deal if you planned on continuing to work. HP would tell you it would be a 3, 6 or 9 months ramp down at lower and lower pay. You couldn't really get another job during that time. If you were planning on stopping work, it was ok. Sadly, a few people asked for 3 months, got told it's 12 months (and too late to back out- once you signed on, HP picked the ramp down period) and then got told they had to stay another year or lose all benefits. It didn't go over well.
Alas, I doubt anything other than a normal termination will be offered any more.