Now that Boeing Co.’s (NYSE: BA) 2015 investor conference is behind us, it is a good time to check and see what analysts had to say about what Boeing had to say. Perhaps most interesting is that no analysts changed their views of the company. Those that believed Boeing was a buy still think so, and the one that thinks the company is a sell did not change its mind.

Buckingham Research summed up the general feeling, noting that Boeing offered a lot of information but not much that was new. According to Leeham News and Comment, in Buckingham’s note following Tuesday’s conference the analysts focused on Boeing’s 777 program. The analysts, and many investors, keep trying to pin down Boeing on its transition plan for the 777 to the 777X that is due to enter service in 2020.

There are two concerns about the 777: first, that margins will degrade as Boeing has to offer the plane at steeper discounts in order to sell 40 to 60 of the planes annually and keep the line open until the 777X is ready. Boeing claims that pricing has stabilized, and Buckingham noted that in its view, “[Boeing] has been able to sustain 777 program margins largely due to effective supply chain management, automation, and productivity initiatives which have resulted in a 30% reduction in factory flow time.”

The other concern is about orders for the 777 and the so-called bridge to 777X. Boeing said that 777 production is about 55% sold in 2017 and admitted that it would be difficult to get new orders for the plan to fill all its open delivery positions. The company says it has flexibility to manage its orders and deliveries, which after 2017 consists mostly of options and letters of intent. This gives the company flexibility, which it can combine with sales campaigns and maintain stable production rates on the 777.

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Buckingham demurs:

We think that’s going to be very difficult. [Boeing] needs to alert its supply chain as much as 18 months in advance of any production rate change. Consequently, 777 orders over the next few months could be critical to [Boeing] and the ability to bridge the production gap between the 777 Classic and 777X. While we believe a modest rate cut (of 1/mo) is likely in the stock, we think [Boeing] could reduce 777 production by 4/mo which we estimate would be a $1.25-$1.50/share impact to [Boeing]’s 2017E [free cash flow].

Last September Buckingham dropped its rating on Boeing from Neutral to Underperform.

Analysts from Wells Fargo share concerns about the changeover from the 777 to the 777X. Here is what the Wells Fargo analysts had to say about the 777 bridge program:

Boeing expects to maintain 777-family production at 100/year (8.3/mo). Beginning in late 2017/early 2018, we expect Boeing to begin layering in 777X units into production. Essentially, Boeing will add “blanks” to the production process because initial 777X manufacturing will take longer than the time for one existing 777. For example, if one 777X is feathered in it may replace two or three 777-300ER production slots. Therefore, Boeing can still assert it has maintained its 8.3/mo production rate, but might be delivering at a lower rate – perhaps 6/mo – and therefore would need to sell fewer units to bridge production to the 777X.

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