A source that spoke with 9to5Mac has indicated that shipments of the fourth-generation iPad with Retina display are arriving at Apple retail locations, with notices that they're to be opened tomorrow.
Reliable KGI Securities analyst Ming-Chi Kuo initially predicted the shift from the iPad 2 to the iPad 4 back in February, suggesting Apple would wind down iPad 2 production during the first quarter of 2014, replacing it instead with the more powerful iPad 4.
Apple originally ceased selling the fourth-generation iPad when the thinner, lighter iPad Air was introduced in October of 2013 and continued to offer the 2011 iPad 2 as its lower-cost tablet option instead. Priced at $399, the iPad 2 is currently offered for $100 less than the $499 iPad Air.
Apple has presumably opted to keep the iPad 2 in its lineup because of its position as the last Apple tablet using a 30-pin adapter, but with its A5 processor and 512 MB of memory, it is significantly less powerful than the iPad 4, which includes Apple’s A6X chip with 1 GB of memory.
With the iPad 2 being replaced by the fourth-generation iPad, Apple's tablet lineup will be all Lightning for the first time. It's also possible Apple's current low-cost iPhone option, the iPhone 4s, will be discontinued at the same time in favor of the 8 GB iPhone 5c, marking the end of the 30-pin adapter in all non-iPod mobile products. Apple's iPod Classic will be the sole device using the adapter if the iPhone 4s and the iPad 2 are replaced with updated options.
Pricing for the 8 GB iPhone 5c and the reintroduced fourth-generation iPad have not yet been revealed, but it is likely Apple will make an announcement on the new products tomorrow.