The Juarez website claims: "Should the I-601 waiver not be approved on the same day as its in person submission and is referred for a future and final review and adjudication, the current processing time is 13-15 months." In my experience, Juarez is taking longer than this on some cases but every waiver is different and preparation is key.
The easy waivers are decided in 2 to 3 months, but the others are shipped from Juarez to Anaheim, California and often take about one year to be decided.
(213) 394-4554 x0 Mr. Shusterman is a former INS Trial Attorney (1976-82) with over 35 years of immigration experience. His response to your question is general in nature, as not all the facts are known to him. You should retain an attorney experienced in immigration law to review all the facts in your case in order to receive advice specific to your case. Mr. Shusterman's statement above does not create an attorney/client relationship.