In a direct communication, the source explained:

We have suspended publication of real yields and the inflation compensation term structure temporarily while we review our estimation, and they will remain unavailable while the review is on going and not complete. We do not know at this time when we will complete the review. [...] Unfortunately there is no replacement series for this.

For these series, the last period is May 15, 2017, but we have not marked the series as discontinued. Moody's Analytics will continue to monitor the situation.

The series reside in the historical catalog (United Kingdom » Financial » Interest Rates » Government yield curve (Gilts) » Forward | Spot » Inflation | Real) and include, for example:

• IR%IIS59MUD.IGBR   = Implied Spot Inflation Rates; Short End - 59 Month, (%)
• IR%GBRS20YUD.IGBR  = Interest Rates Real Spot Government Bond Yield - 20 Year
• IR%IIFI18HYUD.IGBR = Instantaneous Implied Forward Inflation Rates - 18.5 Year

Conversely, the nominal curves remain active, including the summary of eight tenors from three months to 25 years (... » Key Indicators) and the detail (...» Forward | Spot » Nominal), including:

• IR%GBNS10YUD.IGBR  = Nominal spot government bond yield - 10 Year
• IR%GBNF1MUD.IGBR   = Instantaneous nominal forward government bond yield - Short end - 1 month
• IR%GBNS24HYUD.IGBR = Instantaneous nominal forward government bond yield - Long end - 24.5 year

Because catalog locations are subject to change, the upper-right search box on DataBuffet.com provides a "find in catalog" mode that accepts a mnemonic.